Electric discharge tube



April 17, 1934. J. M. UNK m AL ELECTRIC DISCHARGE TUBE Filed Oct. 22, 1930 atented Apr. 17, 1934 UNITED STATES PATENT OFFICE 1,955,396 ELECTRIC DISCHARGE TUBE Application October 22, 1930, Serial No. 490,356 In the Netherlands November 19, 1929 3 Claims.

As is generally known, many electric discharge tubes for receiving or amplifying electric oscillations often present the disadvantage that the discharge phenomena are unfavorably influenced 5 by shocks and vibrations to which the tube is exposed. These vibrations are often brought about, for example, by a loud-speaker placed in the vicinity of the discharge tubes, and give rise to distortion of the signals received by means of the letubes.

If the distorted signals are reproduced by the loud-speaker which is placed in the neighborhood of the discharge tubes, then the distorted sound Waves act in turn upon the discharge tube so that an acoustic back-coupling is established. It goes Without saying that the disturbances and distortions of the signals received, which are caused by vibration of the discharge tube and its electrodes, may be very annoying.

The invention relates to a device comprising an electric discharge tube which is housed in a closed vessel and has for its purpose to obviate the drawbacks above referred to.

According to the invention, an electric discharge tube is suspended in a closed vessel by means of non-rigid threads. It has been found that the electrodes of a discharge tube mounted in this manner are practically prevented from vibrating by external shocks. If it is desired to obtain a construction which is practically entirely free from vibrations, then it may be advisable to suspend the envelope itself within which the discharge tube is suspended in a second envelope by means of threads. If need be, this envelope may also be housed in a similar manner in a third envelope.

It will be obvious that by the term threads referred to in this application are also understood band shaped or similar members.

The invention will be more clearly understood by reference to the accompanying drawing, representing by way of example one embodiment of the invention.

The arrangement shown in the figure comprises an electric discharge tube for receiving or amplifying electric oscillations. The wall of this tube is denoted by l and has sealed to it a stem 2 on which the electrodes, viz., a cathode 3, a grid 4, and an anode 5, are mounted. The envelope 1 is exhausted and sealed in the usual manner.

The discharge tube is housed in a closed vessel which is partly constituted by a bell 6, consisting, for example, of glass and closed at the lower side by the base '7 which is secured to the bulb 6 by means of cement 8 and also connected with the cap 9 to which the various contact pins 10 are fixed. On the base 7 are mounted a number of rods, for example three, two of which are shown on the drawing and denoted by 11 and 12. The rods are connected together by means of a ring 13. To the upper end of these rods are secured several hooks 14, the hooks 15 being fixed at the lower end of the rods. Around the discharge tube is disposed a ring 16, consisting, for example, of so-called insulating tape. Between this ring and the discharge tube are pinched non-rigid threads 17, consisting of damping material, for example,

of silk or elastic material and closed in themselves so that they may be conveniently laid on the hooks 14 and 15. By a suspension by means of flexible threads very favorable results are obtained.

The various leading-in wires 18 connecting the electrodes of the discharge tube with the contact pins 10 are electrically insulated from one other and consist of slack wires, so that they do not constitute a rigid connection between the contact pins and the discharge tube. When the discharge tube is suspended in this manner the vibrations to which the bulb 6, the base '7, or the cap 9 is exposed do not reach the discharge tube, so that the electrodes of this tube do not present objectionable vibrations.

If desired, the envelope 6 in which the discharge tube is housed may be exhausted. The applicants have found, however, that the passage of the vibrations is comparatively only slightly affected by the evacuation of the envelope 6, so that the effect obtained thereby constitutes only a fraction of the eiiect obtained by suspension.

We claim:

1. An electron discharge device comprising an evacuated envelope having a plurality of electrodes mounted therein, a base member and a plurality of upright supports carried thereby, and means connected between the upper and lower ends of each of said supports for resiliently suspending the evacuated envelope from said supports above and out of contact with said base member, said base member having the usual electrode terminals, and electrical connections between said terminals and the electrodes.

2. An electron discharge device comprising an evacuated envelope having a plurality of electrodes mounted therein, a base member and a plurality of supports arising therefrom arranged in spaced relation with respect to the evacuated envelope, an insulating member fitted around the outer surface of the envelope, and elastic means interposed between said insulating member terminals being electrically connected to the electrodes, support members extending from the base member into the space between the envelopes and substantialy co-extensive with the inner envelope, and means connected between the upper and lower ends of said support members for resiliently suspending the evacuated envelope from said support members out of contact with both the base member and the outer envelope.

JACOB MARINUS UNK.

KAREL MARINUS VAN GESSEL.

EKKO OOSTERHUIS. 

